To start dialogue with Bill it will ask you to contact the Cerulean authorities about the disappearance of Ash Ketchum.

Officer Jenny is east (right) of the pokemon center of Cerulean, chatting with her, she will give you some posters searched and asked you to paste on the walls of Cerulean and Pewter. The position of where to paste the posters are marked on your mini map, just move closer to the wall and use the poster in it, after that go back and talk to her again and she will send you to speak to the Bill.

Bill will say it has a tracking device somewhere in Vermilion and tells you to go get it back. The device can be in three different places, the Persians, the right of the lake between Saffron and Vermilion and the right of Vermilion.

Recovering the device back to Bill, where he will give you your reward and a ticket for travel on the S. S. Anne.

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